Few ontologies in the ecological domain exist, but their development can take advantage of gained experience in other domains and from existing modeling practices in ecology. Taxonomies do not suffice because more expressive modeling techniques are already available in ecology, and the perspective of flow with its centrality of events and processes cannot be represented adequately in a taxonomy. Therefore, formal ontologies are required for sufficient expressivity and to be of benefit to ecologists, which also enables future reuse. We have created a formal mapping between the software-supported ecological modeling method and software tool STELLA and ontology elements, which simplifies bottom-up ontology development considerably and has excellent potential for semi-automated ontology development. However, the conducted experiments also revealed that ontology development for ecology is close to being part of ecological research that through the formalized representation of the knowledge more clearly points to lacunas and suggestions for further research in ecology.